Polyolefins such as high density polyethylene (HDPE) homopolymer and linear low density polyethylene (LLDPE) copolymer can be produced using various combinations of catalyst systems and polymerization processes. However, typically the transition metal component of the catalyst system in Ziegler-Natta, chromium, and metallocene based catalyst systems is selected to produce ethylene polymers with specific molecular weight and molecular weight distribution (MWD) characteristics.
It would be beneficial, instead, to control or adjust the molecular weight and molecular weight distribution with another component of the catalyst system, such as an alkylaluminum compound or co-catalyst. Accordingly, it is to this end that the present invention is principally directed.